Half man and half madman, Two-Face was the alias of former Gotham City District Attorney Harvey Dent. After he received brain damage by a mobster's acid, Dent became a bloodthirsty, eccentric, and homicidal maniac with a penchant for using a coin that determined all of his actions.

"We've received a letter from Batman this morning. 'Please inform the citizens of Gotham that Gotham City has earned a rest from crime. But if the forces of evil should rise again, to cast a shadow on the heart of the city, call me."

While Dent questioned mob boss Sal Moroni in court, Moroni managed to retrieve a hidden flask of acid and threw it on Dent. Batman became aware of that plot, and ran through the courtroom to save Dent, but arrived too late. The acid splashed against the left side of Dent's face, and horribly disfigured it, while the right side was protected by his notepad.

The acid burned far enough through Dent's head that part of his brain was damaged, and made him psychotic and homicidal. He developed a second personality, called "Two-Face" and would refer to himself in the plural. Dent was eventually arrested and committed to Arkham Asylum.

Two-Face escaped from his cell on the second anniversary of his arrest, and his escape was discovered by Dr. Burton, who then contacted the GCPD. Two-Face and his thugs robbed the Second Bank of Gotham. They took hostages and looked like they were going to get away when Batman intervened and stopped the robbery. Two-Face trapped him and a guard inside an acid filled safe, but Batman escaped and saved the horrified guard. Batman pursued Two-Face by boarding his helicopter. However, Two-Face escaped before he crashed his helicopter into the Statue of Justice over Gotham Harbor.

At his new hideout, which had decor split in half like his personality, Two-Face had two henchwomen, Sugar and Spice, who worked for him. Spice favored his 'dark', scarred side, while Sugar favored his 'good' side.

Two-Face traveled to the circus looking for Batman. The circus held a fundraiser that was attended by Gotham's elite, and Two-Face concluded that the odds were excellent that at least one of them knew the Dark Knight's identity if they weren't Batman himself-, and he threatened to blow the place up unless his enemy turned himself over (although the subsequent riot in the circus prevented Bruce Wayne from obeying his order). Two-Face was responsible for the origin of Robin because, when the Flying Graysons tried to stop him, they were all killed by him apart from Dick, the youngest Grayson, who went on to join Batman as Robin after he stopped his bomb.

At his hideout, Two-Face met Edward Nygma, who adopted the mantle of the Riddler, where Two-Face initially wanted to kill him for invading his lair, but Riddler stated his case, and Two-Face decided via coin flip whether he killed or allied with him. After his coin landed on heads, Two-Face stole enough money to fund Nygma's company, and the two gained knowledge through the Box and discovered Batman's true identity at Nygma's party. Following that, they traveled to Wayne Manor and the Riddler destroyed the Batcave. Two-Face, on other hand, had his henchmen attack Bruce and Dr. Chase Meridian while he flipped his coin, which kept landing on the good side, and prevented him from doing any wrongdoing. As soon as the scarred side came up, Two-Face fired his pistol at Wayne, which grazed him in the head. Two-Face wished to finish him off, but the Riddler intervened, then they left, kidnapped Dr. Meridian, and left behind a riddle.

At Claw Island, where Two Face hid, Batman and Robin got separated. Robin had the opportunity to kill Two-Face, but didn't want to be like him. Two-Face used that to capture Robin. Two-Face and the Riddler then tried to make Batman choose between Chase and Robin but Batman destroyed The Box, which permanently defeated the Riddler, and saved them both. Two-Face showed up, and was poised to kill them, but Batman reminded him of his coin. Two-Face flipped his coin to decide if he would shoot Batman, but Batman tossed a handful of identical coins into the air. Two-Face panicked and tried to find his coin but stumbled and fell into the pit on a watery bed of spikes. His exact coin then fell good side up into Two-Face's open palm before he sunk underwater, dead.

Three years later, when Bane broke into Arkham Asylum's storage room to get Mr. Freeze's suit, Two-Face's unique costume was glimpsed hanging on a shelf, but it was unclear if that meant that he had survived his fall and was captured or if it was simply a costume that he left behind during his last escape.

This was the only version of Two-Face that did not have a bulging eyeball and exposed teeth on the left side. Rick Baker wanted to portray these iconic qualities early in the design process but was quickly vetoed.

It would be highly unlikely for the acid to scar Harvey's face so symmetrically, even with blocking by a folder. Two-Face would've had to undergone reconstructive/deconstructive surgery to even his scarred side. There is also no precedent for acid damage to cause root follicles growing purple hair, so that was also likely an aesthetic decision made by Two-Face to complete the effect of his duality. In more recent realistic depictions, there is little to no hair at all.

Tommy Lee Jones took over the role for Billy Dee Williams' portrayal of Harvey Dent in Batman. Joel Schumacher disliked the idea of having Williams play Two-Face so much, he decided to pay his acting fee in full as required by his play-or-play contract for any possible sequel featuring the character. Two-Face, like Val Kilmer's Batman, should be considered the same character that appeared in the 1989 film, despite the recast.

"Harvey Two-Face" played up the "two" gimmick to the point where Two-Face even referred to himself in the plural, except for two instances when he said: "I'll call you dead, is more like it!" in response to the Riddler's introduction when he broke into his hideout, and in the film's climatic showdown, when he told Robin: "I'll see you in Hell." while he hung on the edge of a cliff. The other "two" themes of half white and half black were: his hideout; his guns (one automatic and one revolver); his suit, and his two molls Sugar and Spice.

Curiously, unlike other depictions of Two-Face, this one was never revealed to take vengeance against Maroni.

In the comics, Tony Zucco killed Robin's parents, but in the film, Two-Face was the murderer. Zucco didn't appear in the film.

In the comics, whatever Two-Face's Coin landed on that would be final. In a scene of the film, Two-Face continued to flip the coin until he obtained his desired result. That irked many fans of the comics. It was hypothesized that during that scene, Two-Face had many opportunities to kill Batman, and simply flipped his coin for every attempt individually.

Unlike with the Joker and Penguin deaths previously, Two-Face was intentionally killed by Batman's direct agency. Although he attempted to kill Joker by punching him off the building, the resulting death is accidental and happens by chance much the like the Penguin stepping backwards into his toxic waste.

Two-Face's trademark costume was seen in storage at Arkham Asylum in Batman & Robin.

DC Comics artist Joe Quinones and Kate Leth pitched a sequel comic to Batman Returns in 2015 that would have featured Billy Dee Williams' version of Harvey Dent and his transformation into his villainous alter ego Two-Face, poetically retconning the events of Joel Schumacher's films. Ultimately, the comic was rejected by DC.